1. Field of the Invention
This invention relates to a panel sealing system for coating or providing a laminate structure for a panel. In particular, this invention directs itself to a coating or layering for a panel which provides a substantially smooth outer surface for the combined layer or coated structure to permit extended useful life of the panel structure, and to allow ease in cleaning of a panel during its operational lifetime. More in particular, this invention is directed to a panel sealing system which provides for a plastic layer to be heat sealed to a panel member to provide an outer closed cell coating or layering for the panel member. More in particular, this invention relates to a panel sealing system which provides an apparatus where a panel member is mounted on an extension frame and then manually inserted into a heating chamber where the heat sealing takes place. Still further, this invention directs itself to a panel sealing system where a panel member and a sheet of plastic is mounted thereover on an extension section of an apparatus followed by a securing of the plastic in fixed relation to the panel member prior to the heat sealing process. Further in particular, this invention directs itself to a system whereby the securement of the plastic layer to the panel member prior to the heat sealing process allows for a smooth coating to be applied to the panel member and aids in cleaning processes during the lifetime of the panel member. Further, this invention directs itself to an automatic panel sealing system whereby subsequent to heat sealing within a heat chamber, the coated or layered panel structure is automatically removed from the heat chamber to allow insertion of another panel structure in consecutive order. Additionally, this invention directs itself to a system which may be brought to the job site and set up for substantial portability considerations. Additionally, this panel sealing system allows for a centrally located heating chamber which may be adjustable as to heat transferred to the coated or layered panel structure when such is inserted within the heating chamber. Still further, this invention relates to a panel sealing system which allows for insert into the heating chamber from opposing ends and allows for rapid heat sealing of panel structures.
2. Prior Art
Methods and apparatus for coating panel members with a thermoplastic film covering are known in the art. The closest prior art known to applicant includes U.S. Pat. Nos. 3,202,561; 4,447,282; 3,092,203; 3,912,542; 4,894,102; 4,664,737; and, 4,666,540.
In some methods and systems for providing a thermoplastic film covering over a panel member such as shown in U.S. Pat. No. 3,202,561, heat is applied through an electrical resistance type system and the panel and covering are maintained on a bed member through a vacuum fan type arrangement. However, in such prior art methods, the actual heating chamber is not heat adjustable to optimize the heating transfer characteristics in order to heat seal the thermoplastic layer to the panel member in an optimized time frame. Additionally, such prior art systems do not appear to allow for automatic removal subsequent to a predetermined time interval from the heating chamber. Thus, the heat sealing is not optimized and the panel and thermoplastic coating or layer may be maintained within the uncontrolled heat chamber for a non-optimized time which would result in either not providing a complete heat sealing process, or alternatively, in providing excess thermoplastic flow on the panel member which may have the effect of providing a non-smooth surface for the coated panel member.
In other prior art systems such as that shown in U.S. Pat. No. 4,894,102, methods for refinishing building panels are provided. In such prior art systems, plastic layers are applied to panel members, however, such systems do not provide for automatic removal of the panel members subsequent to heating within a heating chamber. Such prior art systems require the operator to remove the relatively hot coated panel members from within the heating chamber in a manual operation which may result in injury due to the fact that such heating chambers maintain a high temperature atmosphere for the heat sealing process. Additionally, such prior art systems do not provide for the heat adjustment within the heat chamber to optimize the overall heat sealing process, as provided in the subject invention concept. Still further, methods and systems such as that provided in U.S. Pat. No. 4,894,102 specifically direct themselves to maintaining the plastic layer member in an completely unrestrained manner. Such systems do not provide for a mechanism whereby the thermoplastic layer is secured in fixed relation to the panel member prior to heating and thus, such prior art systems do not allow for a taut condition to apply which results in a non-smooth panel structure coated member subsequent to the heating process.
Other prior art systems provide for securing blankets or other layers on a panel structure mounted on a vacuum bed member, however, such prior art systems provide for mountings on the side of the overall structure which utilizes a net for holding a layer in a taut condition. Such netting provides for openings through which hooks or other securement mechanisms may be maintained in position. Such mountings are cumbersome and require additional structure other than the closed cell layer which is itself being heat sealed.
In other methods of refurbishing building panels, as shown in U.S. Pat. No. 4,666,540, tiles or panels are initially sprayed with an adhesive and some type of decorative material is attached. The combination is run through some pressure rollers which provide for the bonding. Such prior art systems do not provide for the complete heat sealing and resulting smooth finishes which allows for simplicity in cleaning of the combined panel and layer structure subsequent to the process being completed.